Lady in French is 'dame'. Son in French is 'fils'. To say 'the lady and her son' you should say 'la dame et son fils'.
In French, ladies are called as Mesdemoiselles (plural) Mademoiselle (singular)
J'aime Lady GaGa
copine
"Sweet lady" in French is translated as "douce dame."
Bonne Madame
"Jolie dame"
dame mignonne
Post-dame
Je T'aim
la Dame Argentée
Bonjour belle dame